function Get-FreeExtIPAddress{
Param (
$DataCenter
)
Process{
#========================================================================
#SUB Function search the 3rd Octet
#========================================================================
Function Search-IP-3rdOct {
Param (
[int]$StartSearchNumber,
[int]$EndSearchNumber,
$IPArray )
Process {
$IPSearchComplete = $false
do {
:outerLoop
For ($i = $StartSearchNumber; $i -le $EndSearchNumber; $i++){
Write-Log "--Searching Subnet: $i"
#Build an array of IP's in the $i subnet
[int[]] $allocatedIPsLastOcts = @()
$existingIPs = @($IPArray | where {($_ -split "\.")[2] -eq $i})
foreach ($existingIP in $existingIPs) {
$allocatedIPsLastOcts += ($existingIP -split "\.")[3]
}
$allocatedIPsLastOcts = $allocatedIPsLastOcts | Sort
#$FreeIP = Search-Subnet -allocatedIPsLastOct $allocatedIPsLastOcts
$mylastOctIP = 4
$EmptyLastOctIP = 0
foreach ($allocatedIPsLastOct in $allocatedIPsLastOcts) {
if (!$mylastOctIP) {
$mylastOctIP = $allocatedIPsLastOct
}
$myIPdifference = ($allocatedIPsLastOct - $mylastOctIP)
#search for the hole. if difference is Greater than one, we found a hole
if ($myIPdifference -gt 1) {
$EmptyLastOctIP = ($mylastOctIP + 1)
$IPAddressToAdd = ($existingIPs[0] -split "\.")[0] + "." + ($existingIPs[0] -split "\.")[1] + "."+$i+"." + ($EmptyLastOctIP)
Write-Host "`tFound IP in $i subnet: $IPAddressToAdd"
Write-Log "Found IP in $i subnet: $IPAddressToAdd"
$IPSearchComplete = $true
break outerLoop
}
$mylastOctIP = $allocatedIPsLastOct
}
if ($EmptyLastOctIP -eq 0){
#we didn't find any holes but the subnet might not be full
if ($mylastOctIP -le 254){
$EmptyLastOctIP = $mylastOctIP + 1
$IPAddressToAdd = ($existingIPs[0] -split "\.")[0] + "." + ($existingIPs[0] -split "\.")[1] + "."+$i+"." + ($EmptyLastOctIP)
Write-Host "`tFound IP in $i $IPAddressToAdd"
Write-Log "Found IP in $i $IPAddressToAdd"
$IPSearchComplete = $true
break outerLoop
}
else{
$EmptyLastOctIP = 0
$IPAddressToAdd = $null
write-host "`tIP Subnet $i is Full"
}
}
}
$IPAddressToAdd
}
until($IPSearchComplete)
}
}
#========================================================================
#SUB Function search a particular subnet
#========================================================================
Function Search-Subnet{
Param (
$allocatedIPsLastOct
)
Process {
#$mycount = 1
#$subnetsearch = $false
$EmptyIP = 0
foreach ($allocatedIP in $allocatedIPsLastOct) {
if (!$mylastIP) {
$mylastIP = $allocatedIP
}
$mycurrentIP = $allocatedIP
$myIPdifference = ($mycurrentIP - $mylastIP)
#write-host "$mycurrentIP - $mylastIP = $myIPdifference"
#search for the hole. if difference is Greater than one, we found a hole
if ($myIPdifference -gt 1) {
$EmptyIP = ($mylastIP + 1)
$EmptyIP
#write-host "Found empty IP: $EmptyIP"
break
}
$mylastIP = $allocatedIP
}
if ($EmptyIP -eq 0){
#write-host "No Holes Found"
if ($mylastIP -le 254){
$EmptyIP = $mylastIP+1
$EmptyIP
#write-host "Found empty IP: $EmptyIP"
}
else{
$EmptyIP = 0
$EmptyIP
write-host "`tIP Subnet is Full"
}
}
}
}
#========================================================================
# MAIN Code
#========================================================================
Write-Host "`nSearching for the next free IP Address" -ForegroundColor 'Cyan'
Write-Host "-----------------------------------------------------"
write-host "Data Center:`t" $DataCenter
Write-Host "-----------------------------------------------------"
Write-Log "--IPaddress search starting"
# Find the next available IP address
$IPExtractOK = $false
$manualIPOK = $false
$count = 0
do {
try{
$extnet = Get-ExternalNetwork
$ExtNetView = $Extnet | Get-CIView
$allocatedIPs = $extnetView.Configuration.IpScopes.IpScope[0].allocatedipaddresses.ipaddress
$IPCount = ($allocatedIPs | measure).Count
write-host "--Found $IPCount IP Addresses in use"
$error.clear()
$IPExtractOK = $true
}
catch{
$count++
write-host "--An error has occurred whilst collecting the used IP addresses" -foregroundcolor Red
write-host $error -foregroundcolor Red
#if count is over 3, try and reconnect the server
if ($count -ge 1){
write-host "--IP collection has failed repeatedly... " -foregroundcolor yellow
$IPAddressToAdd = read-host "Enter an IP address to use"
$error.clear()
$manualIPOK = $true
break
}
write-host "--Script will try and recollect the IP's in 5 seconds time..." -foregroundcolor yellow
start-sleep -seconds 5
$IPExtractOK = $false
$error.clear()
}
}
until($IPExtractOK -or $manualIPOK)
#We have 3 datacenters so we have it search based off of it. You can remove this and replace the code with the variables with hard coded figures if you want
if ($IPExtractOK){
if($DataCenter -eq "yourdatacenter"){
$StartOct = $DefinitionyourdatacenterStartIP.Split(".")[2]
$EndOct = $DefinitionyourdatacenterEndIP.Split(".")[2]
$IPAddressToAdd = Search-IP-3rdOct -StartSearchNumber $StartOct -EndSearchNumber $EndOct -IPArray $allocatedIPs
}
elseif($DataCenter -eq "yourdatacenter"){
$StartOct = $DefinitionyourdatacenterStartIP.Split(".")[2]
$EndOct = $DefinitionyourdatacenterEndIP.Split(".")[2]
$IPAddressToAdd = Search-IP-3rdOct -StartSearchNumber $StartOct -EndSearchNumber $EndOct -IPArray $allocatedIPs
}
elseif($DataCenter -eq "yourdatacenter"){
$StartOct = $DefinitionyourdatacenterStartIP.Split(".")[2]
$EndOct = $DefinitionyourdatacenterEndIP.Split(".")[2]
$IPAddressToAdd = Search-IP-3rdOct -StartSearchNumber $StartOct -EndSearchNumber $EndOct -IPArray $allocatedIPs
}
}
if (!$IPAddressToAdd){
$IPAddressToAdd = "0.0.0.0"
Write-Host "ERROR: No IP Found" -ForegroundColor red
Write-Log "ERROR: No IP Found"
$x = Read-host "`nPress ENTER to continue ..."
exit
}
if ($error){
Write-Log "ERROR:"
Write-Log $error
Write-Host "ERROR FOUND" -foregroundcolor Red
$x = Read-host "`nPress ENTER to continue ..."
$error.clear()
}
$IPAddressToAdd
Write-Host "--The next free IP is: "$IPAddressToAdd
Write-Host "--This will be used as the external IP for this org"
Write-Host "--IP Address search complete" -ForegroundColor 'Green'
Write-Log "The next free IP is: $IPAddressToAdd"
Write-Log "--IP Address search complete"
}
}
